7.62x51 vs 308? what is the difference?
7.62x51 vs 308? what is the difference?
Some might have seen my 308 post earlier. I still don't have a rifle that will shoot my silver 308 rounds but in my quest for one I came across somebody who while they wouldn't part with one of their firearms did give me a box of mystery ammo which, according to research I did, is Canadian made nato 7.61x51 made in 1979. Markings are the nato cross, "IVI" and "79". During research I found that apparently the rounds are great for reloading but nothing about what shoots them. Will they fire from a standard 308 or are they made for a specific rifle?
"The deeper sorrow cleaves into your soul the greater it's capacity to contain joy" -DeSade
when in doubt set it on fire.
when in doubt set it on fire.
Re: 7.62x51 vs 308? what is the difference?
None, there is no difference between the two. 7.62x51 will fire in any .308 rifle and any .308 round will fire in any 7.62x51 rifle that I know of.
It dosent matter but the rounds you are talking about sounds like they were going to use them for the M60 machinegun. Are they on a belt?
It dosent matter but the rounds you are talking about sounds like they were going to use them for the M60 machinegun. Are they on a belt?
The way of the fool is right in his own eyes. Proverbs 12:15 KJV
For every thousand people hacking at the branches of evil there is only one hacking at the roots. H
enry David Thoreau
For every thousand people hacking at the branches of evil there is only one hacking at the roots. H
enry David Thoreau
Re: 7.62x51 vs 308? what is the difference?
no belt. Smaller box out of a much larger box. No links. Thanks for the info... one more reason to snag a 308 
"The deeper sorrow cleaves into your soul the greater it's capacity to contain joy" -DeSade
when in doubt set it on fire.
when in doubt set it on fire.
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jrswanson1
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Re: 7.62x51 vs 308? what is the difference?
jim100 wrote:None, there is no difference between the two. 7.62x51 will fire in any .308 rifle and any .308 round will fire in any 7.62x51 rifle that I know of.
It dosent matter but the rounds you are talking about sounds like they were going to use them for the M60 machinegun. Are they on a belt?
No. The 7.62x51 operates at a much lower pressure as they are usually fired in either a semi-auto rifle or a machine gun. I don't shoot .308 ammo out of my milsurp 7.62 NATO rifle as the pressure is too high and since the brass is thinner they tend to break in the chamber.
Jim
Re: 7.62x51 vs 308? what is the difference?
so it is safe to fire 7.62x51 from any 308 or 7.62x51 rifle but not correct to fire 308 from a 7.62x51 rifle? Kinda like the 223/ak thing? or like a regular m700 vs a m24 system? What inexpensive gun will handle 7.62x51?jrswanson1 wrote:jim100 wrote:None, there is no difference between the two. 7.62x51 will fire in any .308 rifle and any .308 round will fire in any 7.62x51 rifle that I know of.
It dosent matter but the rounds you are talking about sounds like they were going to use them for the M60 machinegun. Are they on a belt?
No. The 7.62x51 operates at a much lower pressure as they are usually fired in either a semi-auto rifle or a machine gun. I don't shoot .308 ammo out of my milsurp 7.62 NATO rifle as the pressure is too high and since the brass is thinner they tend to break in the chamber.
Jim
"The deeper sorrow cleaves into your soul the greater it's capacity to contain joy" -DeSade
when in doubt set it on fire.
when in doubt set it on fire.
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gunderwood
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Re: 7.62x51 vs 308? what is the difference?
http://www.6mmbr.com/308win.html
.308 Win vs. 7.62x51--The Straight Scoop
Before we go much further, we want to address the oft-posed question "Are the .308 Winchester and 7.62x51 NATO one and the same?" The simple answer is no. There are differences in chamber specs and maximum pressures. The SAMMI/CIP maximum pressure for the .308 Win cartridge is 62,000 psi, while the 7.62x51 max is 50,000 psi. Also, the headspace is slightly different. The .308 Win "Go Gauge" is 1.630" vs. 1.635" for the 7.62x51. The .308's "No-Go" dimension is 1.634" vs. 1.6405" for a 7.62x51 "No Go" gauge. That said, it is normally fine to shoot quality 7.62x51 NATO ammo in a gun chambered for the .308 Winchester (though not all NATO ammo is identical). Clint McKee of Fulton Armory notes: "[N]obody makes 7.62mm (NATO) ammo that isn't to the .308 'headspace' dimension spec. So 7.62mm ammo fits nicely into .308 chambers, as a rule." You CAN encounter problems going the other way, however. A commercial .308 Win round can exceed the max rated pressure for the 7.62x51. So, you should avoid putting full-power .308 Win rounds into military surplus rifles that have been designed for 50,000 psi max. For more information on this interesting topic, read the following articles: Gun Zone's 30 Caliber FAQ; Cruffler.com Technical Trivia, June 2001; and last, but not least, Steve Redgwell's .308 vs 7.62x51 Analysis, which really provides a definitive explanation. Reloaders should also note that military ammo often is made with a thicker web. Consequently the case capacity of 7.62x51 brass is usually less than that of commercial .308 brass. You may need to reduce recommended .308 Winchester loads by as much as 2 full grains, if you reload with military 7.62x51 brass, such as Lake City or IMI.
sudo modprobe commonsense
FATAL: Module commonsense not found.
FATAL: Module commonsense not found.
Re: 7.62x51 vs 308? what is the difference?
Sorry for the incorrect information katana I thought the were the same. 
Thanks for the save jrswanson and gunderwood.
Thanks for the save jrswanson and gunderwood.
The way of the fool is right in his own eyes. Proverbs 12:15 KJV
For every thousand people hacking at the branches of evil there is only one hacking at the roots. H
enry David Thoreau
For every thousand people hacking at the branches of evil there is only one hacking at the roots. H
enry David Thoreau
Re: 7.62x51 vs 308? what is the difference?
There's "two" kinds of pressure.
One is chamber pressure - which most of the pressure "talk" in reloading manuals is about.
The second is gas system pressure if talking about a semi-automatic.
Some rifles (GI surplus type) are sensitive to gas system pressure.
If you want to buy a GI type surplus rifle (FN FAL, M1A, Cetme, etc.) you can shoot all the surplus 7.62 NATO you want though them. The M1A at least, can be sensitive to commercial ammo and heavy bullets. Stay away from them with the M1A.
The FN FAL has an adjustable gas system but that won't help if the chamber pressures are the issue vs. gas system pressures.
A commercial bolt action rifle would be okay with either cartridge. An M1 Garand rebarreled (and done correctly) would be okay with either cartridge IF you buy one of the adjustable gas plugs for it (The receiver/bolt of the M1 is almost unmatched in strength but the gas system can be damaged by heavy bullets and the slow burning powders used to propel them). Two companies make adjustable gas plugs for the M1, McCann (which I have no experience with) and the Schuster (I have one on my M1 Garand and it works great).
One is chamber pressure - which most of the pressure "talk" in reloading manuals is about.
The second is gas system pressure if talking about a semi-automatic.
Some rifles (GI surplus type) are sensitive to gas system pressure.
If you want to buy a GI type surplus rifle (FN FAL, M1A, Cetme, etc.) you can shoot all the surplus 7.62 NATO you want though them. The M1A at least, can be sensitive to commercial ammo and heavy bullets. Stay away from them with the M1A.
The FN FAL has an adjustable gas system but that won't help if the chamber pressures are the issue vs. gas system pressures.
A commercial bolt action rifle would be okay with either cartridge. An M1 Garand rebarreled (and done correctly) would be okay with either cartridge IF you buy one of the adjustable gas plugs for it (The receiver/bolt of the M1 is almost unmatched in strength but the gas system can be damaged by heavy bullets and the slow burning powders used to propel them). Two companies make adjustable gas plugs for the M1, McCann (which I have no experience with) and the Schuster (I have one on my M1 Garand and it works great).